If you have not noticed it before when you are searching for something on Google be sure to check the top left corner under the Google logo to see if Google is personalizing your search. If you have a Gmail and are logged in while doing a search on Google chances are Google is tailoring the results to generate what Google thinks are the best results for you are based on you past search history. If you look in your “search setting” while logged into your Google account you will see if what elements your results are being based around. Google looks not only at your past history but also your current location so it can try to determine what would be the best search results to display.
If you do not have a Google account you may see Google’s notification feature displaying that the results are not personalized:
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